Control valve assembly for purified water supply system

ABSTRACT

A control valve assembly for use in a reverse osmosis system in which a tank and a pliable barrier are used to define a reservoir having separate confined spaces for purified water and reject water. The barrier when not deformed occupies only a portion of the interior of the tank, and requires a minimum of material to define. The uppermost part of the tank supports a single valve that has a pressurized feed water inlet and outlet, and a movable portion that extends into the interior of the upper interior portion of the tank. Upward movement of the movable portion throttles the rate of flow of pressurized feed water between the inlet and outlet. The barrier in addition of sub-dividing the interior of the reservoir into separate confined spaces of variable volume also serves to physically contact the movable portion and move it upwardly as the first confined space moves towards a last stage in approaching a filled condition to throttle the flow of pressurized feed water through the valve.

CROSS REFERENCE TO RELATED APPLICATIONS

The present application is a continuation of application Ser. No.545,880 filed July 23, 1984, now U.S. Pat. No. 4,595,497, issued June17, 1986, which was a substitute of application Ser. No. 330,186 filedDec. 14, 1981, now abandoned, which in turn was a continuation-in-partof application Ser. No. 219,331 filed Dec. 22, 1980, now abandoned,which was a continuation of application Ser. No. 087,881 filed Oct. 24,1979, now abandoned, which was a continuation of application Ser. No.004,652, filed Jan. 19, 1979, now abandoned, which was a continuation ofapplication Ser. No. 867,363 filed Jan. 6, 1978, and now abandoned.

BACKGROUND OF THE INVENTION

In the past, it has been common practice to utilize a purified waterreservoir that contains a confined space filled with air, with air inthe confined space being compressed as purified water discharges intothe reservoir. The compressed air serves as the motive force todischarge purified water from the reservoir when purified water isrequired. This type of reservoir has the operational disadvantage thatas the reservoir fills with purified water, an increasing back pressureis placed on purified water discharging from the reverse osmosiscartridge, and as a result cannot be used efficiently in areas where thefeed water to be purified is supplied at a relatively low pressure. Thistype of reservoir even in areas where the feed water is at a substantialpressure does not operate efficiently due to the back pressure exertedby the compressed air on purified water discharging from the reverseosmosis cartridge, and the efficiency decreasing as the reservoir fillswith purified water.

In another form of prior art reservoir, the purified water reservoir isan elongate fiber wound vessel that has the interior divided by apliable barrier into first and second longitudinal compartments ofvariable volume, with one compartment containing purified water, and theother compartment capable of receiving pressurized feed water or rejectwater to discharge purified water from the reservoir. Certain prior artreverse osmosis systems that employ such reservoirs have the operationaldisadvantage that after the purified water has remained in the reservoirfor a prolonged period of time, the purified water becomes contaminateddue to osmosis occurring between the purified water and feed water inthe reverse osmosis cartridge. Discharge of reject water or feed waterto the reservoir in this type of assembly is controlled by complicatedhydraulically operated means that are responsive to the pressure of thepurified water. Fiber wound reservoirs are formed as an integral unit,and are not capable of being arranged to utilize the same pliablebarrier when the overall volume of the reservoir is halved as ispossible with Applicant's reservoir. Also, reservoirs of this typeutilize a pliable barrier that is of substantially the same length asthe interior of the reservoir, in contrast to Applicant's barrier thatis only one half the length for a reservoir of the same volume. In otherforms of prior art reverse osmosis assemblies of the above describedtype, excess purified water is discharged from the reservoir to a drainafter the reservoir has been filled.

A major object of the present invention is to provide an inexpensivepurified water reservoir of simple design, one that may be easilydisassembled to permit the interior thereof to be cleaned, preferablyutilizes major components that may be injection molded from a suitablecommercially available polymerized resin, employs a pliable barrier tosubdivide the interior of the reservoir into first and second confinedspaces of variable volume into and out of which purified water andreject or feed water may flow through passages in the reservoir, and onthat substantially eliminates the possibility of leakage due to flangeson the major components including the pliable barrier being gripped witha desired force by a circumferentially extending clamp that may bemanually tensioned to a desired degree.

Another object of the invention is to supply a purified water reservoirin which the major components are a pair of cup shaped bodies that havefirst circular flanges that extend outwardly therefrom in abuttingcontact with a second circular flange that extends outwardly from thepliable barrier that is cup shaped, with the first pair of flanges andthe second flange situated therebetween being gripped by a circularflange to provide a reservoir of a desired first interior volume, andthis volume being reduced to substantially one half while using the samebarrier by substituting a circular closure plate for one of the cupshaped bodies.

Yet another object of the invention is to supply a reservoir that notonly serves to store purified water in a reverse osmosis system, butalso provides a mounting for a valve assembly that is responsive to themovement of the barrier by physical contact, therewith with the valveassembly serving to reduce the rate of flow of feed water to the reverseosmosis cartridge as the reservoir approaches a filled condition withpurified water, and as a result a substantial saving being achieved inthe volume of feed water consumed over a period of time relative toprior art reverse osmosis devices is achieved.

A still further object of the invention is to furnish a purified waterreservoir that permits a reverse osmosis cartridge to operate at optimumefficiency as the only back pressure to which purified water dischargingfrom the cartridge is that due to the weight of feed water or rejectwater in the second confined space above the first confined space, andthis weight decreasing as the first confined space fills with purifiedwater.

SUMMARY OF THE INVENTION

The purified water reservoir assembly is used in conjunction with areverse osmosis apparatus that includes a reverse osmosis cartridge thatis in communication with a source of pressurized feed water and amanually operated faucet that controls the flow of pure water and rejectwater when manually moved from a first to a second position.

The purified water reservoir of the present invention preferablyincludes a pair of identical cup shaped bodies having end pieces andside pieces, with first flanges extending outwardly from the freecircumferential edges of the side pieces, and the reservoir being soillustrated in the drawings. However, it is not essential that the cupshaped bodies be identical in structure. The cup shaped bodies arevertically disposed, with the uppermost cup shaped body in an invertedposition. The pair of first flanges have recesses formed in the adjacentsurfaces thereof.

A pliable barrier is provided that has a second flange that defines acircular bead that is removably disposed in the pair of grooves, and thesecond flange having a cup shaped member extending therefrom that isdisposed in the uppermost one of the cup shaped bodies when the pliablebarrier is not deformed. A circumferentially extending clamp ofgenerally U-shaped transverse cross section removably engages the firstpair of flanges and by manually operated tightening means provided onthe clamp it may be tensioned. As the clamp is tensioned the outerportions of the first pair of flanges are drawn towards one another toforce the first pair of recessed flanges into pressure sealing contactwith the bead on the second flange. The cup shaped barrier serves incooperation with the pair of cup shaped bodies to define first andsecond confined spaces of variable volume. An opening is formed in thelower one of the cup shaped bodies that has a fitting mounted therein topermit purified water to discharge into and out of the first confinedspace. The uppermost one of the cup shaped bodies preferably has anopening formed in the end piece thereof, with this opening having avalve assembly mounted thereabove and sealingly secured to the endpiece, which valve assembly is in communication with a source ofpressurized feed water. The valve assembly includes an outlet that is incommunication with the inlet of the reverse osmosis cartridge.

The valve assembly includes a vertically movable valve member thatextends downwardly into the second confined space of the purified waterreservoir, and the valve member supporting a circular plate that is ofsubstantially greater area than the portion of the valve membercontacted by the pressurized water from the source thereof. The valveassembly when the valve member is in a first position obstructscommunication between the feed water inlet and feed outlet of the valveassembly, and when in a second position establishes communicationbetween the feed water inlet and feed water outlet. As the valve membermoves from the second towards the first position, the valve memberserves to throttle the rate of flow from the feed water inlet of thevalve assembly to the feed water outlet. The first confined space as itfills with purified water moves the barrier upwardly, and prior to thefirst confined space reaching the filled position, the barrierphysically contacts the plate. Due to the differential in area of theplate to the upper end of the valve member that is in communication withthe pressurized feed water, the valve member is moved upwardly from thesecond towards the first position even though the pressure of purifiedwater in the reservoir is far less than that of the feed water. As thevalve member so moves upwardly due to contact of the barrier with theplate, the rate of flow of pressurized feed water to the reverse osmosiscartridge is throttled. When this condition is reached, the pressurizedfeed water flows to the reverse osmosis cartridge at a greatly reducedrate relative to the rate it flows when the valve is in the secondposition. Due to the operation of the valve assembly as above described,a minimum of feed water is wasted after the purified water substantiallyfills the first confined space.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a longitudinal cross sectional view of the purified waterreservoir showing a throttling valve assembly supported on the upperportion thereof, and diagrammatically indicating the communicationbetween the valve assembly, the source of pressurized feed water, thereverse osmosis cartridge, and also indicating the flow of purifiedwater from the cartridge as well as reject water, both to the manuallyactuated valve assembly and to the reservoir;

FIG. 2 is an enlarged fragmentary vertical cross sectional view of aportion of a first assembly that is moved from a second open positiontowards a closed first position by physical pressure contact with apliable barrier as a first confined space expands towards asubstantially filled position with purified water, and the first valveassembly including means to move it to the first position if thepressure of reject water or feed water in the second confined spacerises above a predetermined magnitude;

FIG. 3 is an enlarged fragmentary view of a second form of the valveassembly and illustrating a second structure for moving the valve memberto the first position when the pressure on reject water within thereservoir exceeds a predetermined magnitude;

FIG. 4 is the same view as shown in FIG. 3, but with the valve member ina second position;

FIG. 5 is a diagrammatic view of the purified water reservoir that has apurified and reject water inlet and outlet that are separate and apartfrom the valve assembly that includes a pressurized feed water inlet andfeed water outlet;

FIG. 6 is a second diagrammatic view of the purified water reservoir,with the reject water discharging into the second confined space flowingtransversely thereacross to discharge through an outlet in the upper cupshaped body and then through a flow restrictor;

FIG. 7 is a third diagrammatic view of an arrangement in which thepressure of feed water is used to discharge purified water from thereservoir;

FIG. 8 is a fourth diagrammatic view of the use of a purified waterreservoir in a reverse osmosis apparatus;

FIG. 9 is a fifth diagrammatic view of a purified water reservoir thatis similar to that illustrated in FIG. 5, but with the reservoir beingbut half the capacity to that shown in FIG. 5;

FIG. 10 is a sixth diagrammatic view of a purified water reservoir thatis similar to that shown in FIG. 8, but with only half of the capacityof the reservoir illustrated in the last mentioned figure.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

The purified water reservoir R of the present invention as may best beseen in FIG. 1 is formed from two vertically disposed cup shaped bodiesB and B' that preferably are of identical structure. Each of the cupshaped bodies B and B' is preferably formed from a rigid polymerizedresin, and due to being of identical structure may be injection moldedusing the same mold.

Each of the cup shaped bodies B and B' being of identical structure willhave identical components, and only the cup shaped member B will bedescribed in detail, with the numbers used in conjunction with thisdescription being also used on the cup shaped member B', but with primesadded thereto. The cup shaped member B includes an end piece 10 that hasa generally cylindrical side wall 12 extending outwardly from thecircumferential edge thereof, and the side wall terminating in anoutwardly extending circular first flange 14. The first flange 14 has anexternal flat surface 16 in which a circumferentially extending groove18 is defined. The end piece 10 has a recessed center portion 20 asshown in FIG. 1.

A pliable barrier C is provided that includes a cup shaped portion 22that when not deformed substantially fills the interior of the cupshaped member B as shown in FIG. 1. This portion of the barrier C isidentified by the numeral 22, and has a second flange 24 extendingoutwardly from the free circumferential edge thereof, and the secondflange having a bead 26 extending outwardly from the opposite sidesthereof. The bead 26 is disposed in the grooves 18 and 18' when thefirst flanges 14 and 14' are adjacently disposed. When the first flanges14 and 14' are so disposed, the cup shaped member B will occupy aninverted position directly above the cup shaped member B' as shown inFIG. 1.

A clamp L is provided as shown in FIG. 1 which includes acircumferentially extending strip 28 that has a web 30 from which twooppositely angled arms 32 and 32' extend outwardly. The web 30 has thefree ends thereof separated by a space 34 as shown in FIG. 1. The freeends of the web 30 have lugs 36 and 38 extending outwardly therefromthat have aligned openings therein. The lug 36 has a screw 40 thatextends longitudinally therethrough towards the lug 38 to pass throughan opening 42 therein, and the screw being engaged by a nut 44. Head 45of screw 40 abuts against lug 36. By rotating screw 40 relative to thenut 44, the clamp L is tensioned circumferentially, with the arms 32moving inwardly relative to the pair of first flanges 14 and 14' toforce the outer portions of the flanges towards one another and causethe flanges to sealingly engage the bead 26 that is situated within thegrooves 18 and 18'. The barrier C cooperates with the cup shaped membersB and B' to define a first confined space 46 and second confined space48. The cup shaped members B and B' each have raised center portions 96that may be cut therefrom if desired. In FIG. 1 it will be noted thatthe lower cup shaped body B' has the raised portion 96 remainingtherein, while it has been removed in the upper cup shaped member B andreplaced by a valve assembly E that is bonded to the end piece 20 byconventional means.

The first form of valve assembly E is shown in FIG. 1 and in greaterdetail in FIG. 2 includes a body 51 that has a vertically extendingpressurized feed water inlet 52 that terminates on the lower end in aring shaped valve seat 54. A first bore 56 extends downwardly in thebody 51 from the seat 54 and terminates in a body shoulder 58 from whicha second vertical bore 60 aligned with but of greater diameter than thefirst bore 56 extends downwardly.

The first valve assembly E includes an elongate valve member 64 that hasan upwardly disposed first portion 64a that has a resilient member 66mounted on the upper end thereof, which resilient member may sealinglyengage the seat 54 when the valve member 64 is in a first position.Valve member 64 includes a second portion 64b disposed below the firstportion 64a but of larger diameter, which second portion supports anumber of resilient sealing rings 70 that are in slidable sealingcontact with the first bore 56.

The second valve member portion 64b develops into a piston 68 thatsupports a number of circumferentially extending sealing rings 71 thatslidably and sealingly engage the second bore 60. A ring shaped stop 72is mounted in the valve body 51 as shown in FIG. 2 and limits thedownward movement of the piston 68. The valve member includes a thirdportion 74 that extends downwardly from the piston 68 and on the lowerend supports a circular plate 76 of substantially greater diameter thanthe portion of the resilient member 66 that is exposed to pressurizedfeed water W when in engagement with valve seat 54. The plate 76 as seenin FIG. 2 includes a number of circumferentially spaced, upwardlyextending, inverted cup shape members 78 that have upper ends 80 inwhich centered openings 82 are formed. The portion of second bore 60above piston 68 has the air pressure therein equalized with that of theambient atmosphere due to an air vent passage 62 shown in FIG. 2.

A number of screws 84 extend upwardly and slidably through the opening82 to engage tapped metal inserts 86 supported in the valve body 51 asshown in FIG. 2. The screws 84 have the heads 88 thereof disposed withinthe inverted cup shaped member 78, and the plate 76 may move upwardlyand downwardly relative to the screws 84. A helical spring 90 encirclesthe third portion 74 of the valve member 64 and at all times is inabutting contact with the stop 72 and the upper surface of the plate 76.A vent passage 62 is formed in the valve body 51 and communicates withthe upper portion of the second bore 60 as shown in FIG. 2 to at alltimes maintain the air pressure in the second bore 60 above the piston68 at substantially the same pressure as that of the ambient atmosphere.The vent opening 62 also serves to permit any water that may have beendrawn upwardly above the piston 68 to be ejected through the vent 62when the piston 68 moves upwardly to a position adjacent the bodyshoulder 58. In FIG. 2 is would be seen that the valve body 51 includesa feed water discharge passage 94 that communicates with the first bore56 below the valve seat 54.

When pressure of reject water U in the second confined space 48 risesabove a predetermined magnitude, the pressure exerts an upward force onthe lower surface 68a of the piston 68 that is sufficient to overcomethe compression of the spring 90 and also overcome the downward forceexerted by the pressurized feed water W on the resilient member 66 andthe upper surface of the second valve member portion 64b. This excessand undesired pressure of the reject water results in the valve member64 being moved upwardly within the valve body 51 for the resilientmember 66 to assume a first position where it sealingly engages valveseat 54 and prevents further flow of reject water U to the secondconfined space 48. This concept is of importance when the pair of cupshaped members 12 and 12' are formed from a polymerized resin, and it isnot desired to subject the latter to greater than a predeterminedinternal pressure when the cup shaped bodies B and B' are assembled todefine the reservoir assembly R as shown in FIG. 1.

The recessed center portions 20 of end pieces 10 have center areas 96that may be cut therefrom to define stepped circular openings 98 inwhich the base 100 of the valve body 51 may be sealingly supported byconventional bonding means as shown in FIG. 2.

Although the purified water reservoir assembly may be used with variousforms of reverse osmosis assemblies as will later be explained, it ispreferable to use it with a reverse osmosis cartridge Y as shown in FIG.1, and a manually operated purified water and reject water controldevice A that is described and claimed in my co-pending patentapplication Ser. No. 573,155 filed May 1, 1984 entitled "COMBINEDPURIFIED WATER DISPENSING DEVICE AND REJECT WATER CONTROL DEVICE", nowU.S. Pat. No. 4,585,554, issued Apr. 29, 1986.

The reverse osmosis cartridge Y as may be seen in FIG. 1 includes acylindrical shell 175 that has an upper end piece 176 and lower endpiece 178. The shell 175 has a partition 180 in the upper interiorportion thereof that cooperates with the shell and upper end piece 176to define a confined space 188 that is filled with activated carbon 190that removes gases such as chlorine and the like from the purifiedwater. The interior of the cylindrical shell 175 below the partition 180has a reverse osmosis membrane 182 therein that extends around a tube184 in which longitudinally spaced perforations 186 are defined. Thetube 184 extends upwardly above the partition 180 into the confind space188 to terminate in an end piece 184a. Perforations 186 are formed inthe tube 184 that extends above the partition 180 into the confinedspace 188. The end piece 176 has an upper purified water discharge tube114 projecting downwardly into the confined pace 188, with the uppertube 114 terminating on the lower end in an end cap 114a. The portion ofthe tube 114 within the compartment 188 has perforations 186 therein.

The discharge of purified water P from the first confined space 46 andthe flow of reject water U to the drain or to the second confined space48 is preferably controlled by the purified water dispenser A shown inFIG. 1, which is described in detail in my co-pending application Ser.No. 573,155 filed May 1, 1984, now U.S. Pat. No. 4,585,554.

When the pressure on the feed water W has moved the valve E to thesecond position shown in FIG. 2, the feed water which is under pressureand may contain chlorine flows through the discharge 94 in valve E to aconduit 208 that is in communication with the interior of cartridge Yabove membrane 182 and below partition 180 to be subdivided intopurified water P and reject water U. The purified water P may enteropenings 186 in tube 184 to flow through a conduit 212 to enter afitting 213 that is affixed to the lower cup shaped body B' as shown inFIG. 1, and communicates with the first confined space 46. Purifiedwater P after entering openings 186 in tube 184 may flow upwardly intube 184 to discharge through opening 184a and after flowing throughactivated carbon 190 in the space 188 enter openings 186 in a tube 114that extends through top 176 to flow through conduit 214 to a purifiedwater inlet in the purified water and reject water control unit A.

Reject water U flows through a conduit 215 to an inlet 162, and when thehandle 185 of the purified water dispenser A is in an upper firstposition the reject water is directed through flow restrictors (notshown) in the dispenser A to flow through a discharge conduit 250 to thedrain. The dispenser A includes an inverted J shaped tubular member 172through which purified water P discharges when the handle 185 movesdownwardly to a second position.

The purified water dispenser A includes a reject water passage that by aconduit 226 is in communication with a passage 217 in the top 10 of cupshaped body B that is at all times in communication with second confinedspace 48. When the handle 185 is in the upper first position a valvemember (not shown) in the purified water dispenser A obstructscommunication between conduit 214 and spout 172.

Upon the handle 185 being moved downwardly to a second positioncommunication is established between conduit 214 and spout 172.Concurrently, one of the flow restrictors (not shown) in purified waterdispenser A is by-passed and reject water U can flow at a rapid ratethrough conduit 215, purified water dispenser A, passage 174, conduit226, to the passage 217 into second confined space 48. This rapid flowof reject water U in part takes place through membrane 182, and as aresult foreign material is washed therefrom.

The flow of reject water U into second confined space 48 results in adownward force being exerted through the barrier C onto purified water Pin first confined space 46. Purified water is accordingly forced fromthe first confined space 46 through conduit 212 into tube 174 todischarge through opening 186 above partition 180 to flow throughactivated carbon 188 to have any chlorine therein removed therefrom. Thechlorine free purified water now flows through tube 114 and conduit 214to inlet 134 and through purified water dispenser A to the spout 172 todischarge therefrom.

When the above described operation takes place the top portion ofbarrier C moves downwardly in reservoir R out of pressure contact withplate 76, and the force of feed water W on valve member 64 moves thevalve member downwardly to permit an unobstructed flow of feed waterfrom inlet 52 to outlet 94 and conduit 208.

When the first confined space 46 is substantially filled with purifiedwater P and the top of barrier C is in contact with plate 76, theinitial force exerted on purified water P in first confined space 46when handle 185 is moved downwardly from a first to a second positionwill be the force transmitted to the barrier by the plate as the valve Emoves from a first to a second position.

When the handle 185 of the purified water dispenser A is moved from thesecond to the first position, purified water ceases to discharge fromspout 172, and the purified water P from reverse osmosis cartridge Yflows to the first confined space 46. The first confined space nowstarts to expand and the second confined space 48 to contract. Thepurified water P is pressurized in expanding confined space 46 to theextent that it exerts an upward force through barrier C on reject waterU to force the reject water through conduit 226 to enter the purifiedwater dispenser A through passage 174 and then discharge therefromthrough drain line 250, all of which is described in detail in myco-pending application previously identified.

As the first confined space 46 approaches a filled condition the barrierC physically contacts plate 76 and moves valve member 64 towards thefirst position to throttle the flow of feed water W to the reverseosmosis cartridge Y. The valve member 64 approaches but does not reachthe first position, and as a result there is a throttled flow of feedwater W to the membrane 182 that is sufficient to maintain it in a moistcondition.

Should the pressure of reject water U in the second confined space 48exceed a predetermined pressure, a force will be exerted on the surface68a of piston 68 sufficient to move the valve member 64 to a fullyclosed first position. Such a limitation on the internal pressure towhich the reservoir R is subjected is of importance when the cup shapedbodies B and B' are injection molded from a polymerized resin. Thepiston 68 assures that the reservoir R will never be subjected to aninternal pressure that would result in the rupture or breakage thereof.

An alternate form E-1 of the valve is shown in FIGS. 3 and 4 andincludes substantially all of the elements common to valve E. Elementsin valve E-1 common to valve E are identified by the numerals previouslyused, but which are identified by primes being added thereto.

In valve E-1 which is shown in the first or closed position in FIG. 3and the second position in FIG. 4, the stop 72 is eliminated, and thepiston 68 replaced by a cup shaped body 68', that contains the spring90' in abutting contact with the bottom thereof and the body shoulder58'. The cup supports a resilient sealing ring 70' on the exteriorthereof. When the pressure of reject water U in confined space 48 is ofa predetermined magnitude, the force exerted on the bottom 68a' of thecup 68' is sufficient to move the valve member 64' to the first positionshown in FIG. 3.

The reservoir R has been described previously for use with my purifiedwater dispenser, but as may be seen diagrammatically in FIGS. 5 to 10inclusive, it may be used with other reverse osmosis systems.

In FIG. 5 a reservoir R-1 will be seen that reject water U may flow intoand out of the second confined space 48 through a separate conduit 300that is in communication with second confined space 48.

The reservoir R-2 is illustrated in FIG. 6 as having a conduit 302through which reject water U flows to the second confined space 48 andexits therefrom through a conduit 304 that communicates with a flowrestrictor 306.

In FIG. 7 the reservoir R-3 a pressure sensitive valve 308 is shownupstream from valve E, which valve is normally open, but which closeswhen the pressure of reject water U rises above a predeterminedmagnitude. Valve 308 is connected to confined space 48 by a conduit 310.A reject water inlet and outlet 312 is in communication with secondconfined space 48 and a flow restrictor (not shown).

In FIG. 8 the reservoir R-4 is shown with a reject or feed water passage320 that communicates with second confined space 48 and permits flow ofreject or feed water W either into or out of the second confined space.A tubular tee 322 is shown in FIG. 8 that has first, second and thirdlegs 322a, 322b and 322c. Purified water P flows through leg 322 and mayenter first confined space 46 through third leg 322c or flow through leg322b to a desired destination.

A reservoir R-5 is shown in FIG. 9 in which the lower cup shaped body B'is replaced by a closure plate Z that has the peripheral edge thereof,second flange 24 and first flange 14 sealing gripped by a circular clampL. A tubular member 330 is supported from plate Z and is incommunication with first confined space 46. Tubular member 330 permitspurified water P to discharge into and out of first confined space 46.Reject water may flow into and out of second confined space 48 through aconduit 322. The reservoir R-5 permits the same barrier C to be used inthe forms of the invention previously described, but with the volume ofthe reservoir R-5 being but substantially one half of reservoir R orR-1.

The reservoir R-6 is the same as reservoir R-4 but with the cup shapedbody B' replaced by the closure plate Z.

The use and operation of the inventions have been described previouslyin detail and need not be repeated.

The invention claimed is:
 1. A purified water supply system, for use inproviding purified water from a supply of feed water under pressure,said system comprising:a reservoir tank having a pliable barrierdividing the interior thereof into a reject water chamber and a purifiedwater chamber, said reject water chamber being separated by said barrierfrom said purified water chamber; a reverse osmosis unit for receivingand processing feed water to produce purified water and reject water; acontrol valve mounted on said reservoir tank and including a valve bodydefining a feed water inlet for connection to the supply of feed waterand a feed water outlet for connection of feed water to said reverseosmosis unit, and a valve member within said valve body for movementbetween first and second positions respectively preventing andpermitting flow of feed water from said feed water inlet to said feedwater outlet, said valve member including a first portion of relativelysmall cross sectional area exposed to the pressure of feed water at saidfeed water inlet and a pressure plate of substantially larger crosssectional area disposed within said reject water chamber in a positionfor contact by said barrier to displace said valve member toward saidfirst position when said purified water chamber reaches a substantiallyfull condition; means for delivering purified water from said reverseosmosis unit to said purified water chamber; and dispensing valve meansmovable between open and closed positions, said dispensing valve meansin said open position including means for communicating said purifiedwater chamber to a dispensing outlet for use and for communicatingreject water from said reverse osmosis unit to said reject water chamberat a substantial flow rate, whereby the reject water within said rejectwater chamber acts through said barrier against the purified waterwithin said purified water chamber to force the purified water thereinto flow to said dispensing outlet, said dispensing valve means in saidclosed position further including means for preventing communicationbetween said purified water chamber and said dispensing outlet and forcoupling said reject water chamber to a drain substantially without backpressure applied to said reject water chamber, whereby the pressure ofthe feed water acting against said first portion of said valve membernormally maintains said valve member in said second position to permitflow of feed water to said reverse osmosis unit and resultant productionof purified water supplied to said purified water chamber to fill saidpurified water chamber with minimum back pressure and simultaneousdischarge of reject water from said reject water chamber until saidpurified water chamber reaches the substantially full condition and saidbarrier contacts said pressure plate of said valve member to displacesaid valve member toward said first position throttling the flow of feedwater from said feed water inlet to said feed water outlet.
 2. Thepurified water supply system of claim 1 wherein said dispensing valvemeans includes conduit means having flow restrictor means therein, saidconduit means coupling reject water from said reverse osmosis unit tosaid drain with a predetermined back pressure when said dispensing valvemeans is in said closed position.
 3. The purified water supply system ofclaim 2 wherein said conduit means further couples the reject water fromsaid reverse osmosis unit to said reject water chamber with a backpressure substantially less than said predetermined back pressure whensaid dispensing valve means is in said open position.
 4. The purifiedwater supply system of claim 1 wherein said valve body defines a firstbore communicating between said feed water inlet and said feed wateroutlet and defining a valve seat therebetween, said first portion ofsaid valve member including means for sealing seated engagement withsaid valve seat.
 5. The purified water supply system of claim 4 whereinsaid first portion and said pressure plate of said valve member arepositioned generally at opposite ends of said valve member.
 6. Thepurified water supply system of claim 1 wherein said control valvefurther includes means responsive to the pressure of reject water withinsaid reject water chamber to displace said valve member toward saidfirst position when said pressure within said reject water chamberreaches a predetermined threshold.
 7. The purified water supply systemof claim 1 wherein said barrier is spaced from contact with saidpressure plate when said purified water chamber is filled to a levelless than said substantially full condition.